1. Field of the Invention
The present invention relates to a method of therapy and diagnosis of atherosclerosis, particularly to a method of therapy and diagnosis of atherosclerosis based on the relationship between microRNA let-7g and lectin-like oxidized low-density lipoprotein (LOX-1).
2. Description of the Related Art
Cardiovascular diseases, generally referring to diseases, disorders and conditions involved in the cardiovascular system, is a common issue to people in developed countries. It is believed that the pathogenesis of atherosclerosis plays an important role in cardiovascular diseases.
Atherosclerosis is characterized by chronic inflammation, and lipid-rich plaques in blood vessel walls. Generally, the accumulation of oxidized low-density lipoprotein (oxLDL) in vessel walls stimulates the production of various proinflammatory mediators, such as IL-8 and MCP-1, leads to inflammatory, proliferation and migration of aortic smooth muscle cells, and finally affects the circulation of blood to result in multiple diseases.
It has been reported that a scavenger receptor, also known as lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), plays a significant role in the pathogenesis of atherosclerosis, and which can bind with oxLDL and mediate the internalization, as well as the pathological changes of oxLDL in blood vessel walls. However, the detailed mechanism and relationship between oxLDL and LOX-1 has not been fully understood yet. As a result, conventional therapies of atherosclerosis only can avoid the aggravation of atherosclerosis by providing either appropriate medications or basic lifestyle change, for example low-fat diet, to reduce high level of cholesterol or lipoprotein. Nevertheless, it is still lack of a directly and effectively therapeutic strategy to improve the proliferation and migration of vascular smooth muscle cells.
On the other hand, conventional diagnosis of atherosclerosis generally based on patients' history, blood pressure and the physical properties of arteries. They are mainly identified by measuring the flexibility or diameter of arterial vessels walls by using supersonic diagnostic set or phonocardiograph. However, the conventional diagnosis of atherosclerosis has problem in specifically detecting atherosclerosis at early stage.
Hence, there is a pressing need of providing a new strategy of therapy and diagnosis of atherosclerosis, for the sake of rapidly and specifically identifying people at high risk of atherosclerosis, significantly improving atherosclerosis, and finally reducing the incidence to stroke, hypertension, and myocardial infarction.
MicroRNAs, being a novel class of endogenous, small and non-coding RNAs, are widely found in organisms and generally control gene expression thereof. Precisely, microRNAs will specifically target to particular genes and bind to their 3′ UTR region for up-regulating or down-regulating the gene expression of the particular genes. To date, microRNA let-7 has nine family members in human beings, and plays a crucial role in cell proliferation, and cancer, wherein the pivotal role of microRNA let-7g in the regulation of Ras gene and liver cancer has been well-studied. MicroRNA-let7g is generally found in cells in the form of pre-le7g as SEQ ID NO. 1, and which is further processed of enzymetic digestion to obtain a mature form of microRNA-let-7g, as set forth in SEQ ID NO. 2. Recently, microRNA let-7g is used as a new therapy of cancer, and has been put to use in developing cancer related medication or treatment.